The present invention is generally directed to a magnetic head in which a pair of magnetic gaps are disposed in parallel, and more particularly, to a magnetic head suited to record an image into and reproduce an image from a magnetic recording medium such as a rotary magnetic sheet or the like.
Recently, an electronic still camera system has been developed and much attention is given to it. This type of system is typically arranged such that: an object to be imaged is electronically still-photographed by a combination of an imaging device such as a solid imaging device and an image pickup tube, and a recording device employing an inexpensive magnetic sheet as a recording medium, the recording capacity of which is relatively large; the still-photographed image is then recorded on the rotary magnetic sheet; and reproduction of the recorded image is effected by a separately provided television system or a printer.
A 2CH (channel) magnetic head is used for recording an image signal into the magnetic sheet and reproducing it therefrom. There are caused some problems inherent in such a magnetic head.
To be specific, in the case of recording and reproducing the image, the magnetic head is brought into contact with the magnetic sheet which rotates at a high speed. At this time, the magnetic head comes into contact with the magnetic sheet while protruding the magnetic head towards the magnetic sheet, and it follows that the magnetic sheet near the contact position is curved in accordance with an amount of protrusion thereof.
As a result, a condition of contact between a magnetic gap formed in a slide surface of the magnetic head and the magnetic sheet recording surface is likely to be deteriorated. In some cases, this may lead to a recording or reproducing mistake. In order to eliminate the above-mentioned problems, there is proposed a magnetic head in which the sliding surface of the head is formed in a spherical configuration. This method does not, however, provide a satisfactory approach to such problems.
When the magnetic head is in contact with the magnetic sheet, angular portions of the magnetic head impinge upon the recording surface of the magnetic sheet. Then, a degree to which the magnetic sheet is curved fluctuates, and the contact between the magnetic gaps and the magnetic sheet is thereby deteriorated. Therefore, the recording/reproducing process can not stably be performed. The unnecessary impingement of the magnetic head upon the magnetic sheet may damage the magnetic sheet. This also may be one of the reasons why an amount of abrasion of the magnetic head augments.
The magnetic sheet contacts the magnetic head when rotating, and simultaneously the magnetic head moves in a track-width direction (radial direction). Therefore, a configuration and a size of the magnetic head and the spherical shape of the head slide surface are required to be examined in at least two directions, i.e., the magnetic sheet rotational direction and the track-width direction.